Dispensing machines need a variety of light sources, including optical sensing to discriminate the currency bills being fed into the dispensing machine, indicating the status of whether a particular product is available, displaying instructions for operating the dispensing machine, including how a currency bill should be inserted, or displaying an advertisement of the product or trade name.
Although incandescent light bulbs are currently popular light sources for dispensing machines, there are some inherent shortcomings in their application. Thus, there is a need to find a different light source for dispensing machines. For example, the incandescent bulb's life expectancy is quite short in comparison to that of a Light Emitting Diode (LED) which can be expected to last approximately five to ten times longer. Therefore, there would be a reduction in replacement labor costs if LEDs were used as the light sources.
LEDs are much more efficient at converting electrical power into usable light. This is because LEDs are monochromatic; they emit light within a very narrow set of wavelengths rather than waste power emitting light over a wide frequency spectrum. This characteristic makes an LED light source an energy saving device which saves money in electric bills. In gaming casinos where there are thousands of dispensing machines such as gaming machines and money changing machines, the total energy savings can be significant.
The power conversion inefficiency of incandescent lights contributes to the problem of heat damage to surrounding components and the housing structure of the light. Since a relatively large quantity of input power into the incandescent light is not converted into usable light, the unusued power dissipates as heat to the light's surroundings. In its application to dispensing machines where the light source is usually enclosed, heat damage to surrounding components, such as melted plastic parts, dried-up electrical wires, etc., or to the housing structure is more probable. LEDs, with their much lower power requirements and their more efficient power conversion eliminates some heat damage by its reduction in heat emittance.
Also, unlike the incandescent bulb which typically uses a metal filament placed inside a glass bulb, the LED is constructed out of semiconductor materials which are extremely rugged. Dispensing machines are frequently subject to abuse by its users. In particular, it is not uncommon for a user to hit a dispensing machine because the wrong change or the wrong product was delivered. And, an angry gambler's fist may delivere blows to a gaming machine, causing the metal filament or the glass bulb of an incandescent light to break. In dispensing machines with large quantities of cash, vandalism acts such as trying to kick open the machine are likely to cause the incandescent light to break. There are several more advantages to using LEDs as the light sources of dispensing machines. Only a few are mentioned above.
The above-mentioned shortcomings are overcome by the present invention as discussed hereafter.